Lucent Technologies 555-230-220 manual Issue 7 March 1998 A-61

Call Scenarios and Applications

Outgoing Call over ISDN Trunk that Results in an ISDN Progress Message

This section presents the call flow for an outgoing call over an ISDN trunk that traverses a non-ISDN network(s) before it reaches its destination. Station 4567 initiates an outgoing call to an external destination. Station 4567 has Domain Control active and uses the Auto Dial capability to initiate the call (see Figure A-17).

When a call leaves the ISDN network, an ISDN PROGress message is sent from the PRI network to the ECS and subsequently to the ASAI Adjunct Processor. The ECS sends the contents of the PROGress message in a Cut-Through Event Report. Multiple PROGress messages may be sent for a call; each one is mapped into a Cut-Through Event Report.

For a call that has resulted in a Cut-Through Event Report being generated, the Alerting Event Report is optional. A Connected and/or Drop Event Report is always sent as long as the call utilizes the ISDN facilities.

DEFINITY ECS

non-ISDN	External Endpoint
Network	(ISDN Trunk)	call_id=60

x4567

Figure A-17. Call Flow for Outgoing ISDN Call that Traverses a non-ISDN Network

Issue 7 March 1998 A-61